1. Field of the Invention
The invention concerns an articulated boom for a mobile concrete pump comprising at least five mast arms pivotable relative to each other about horizontal rotation axes, wherein the first respective mast arm is articulated to a mast stand so as to be pivotable about a horizontal rotation axis (A), said mast stand being rotatable about a vertical axis, the last mast arm having no articulation joint, wherein the mast arms can be folded relative to each other in groups in the manner of a Z-fold or a coil-type fold for transport purposes.
2. Related Art of the Invention
A concrete distribution mast of this type is known (DE-B-3446290), wherein all mast arms can be folded against each other about their articulation axes in the manner of a Z-fold. This concrete distribution mast has a great reach and can be employed both in low construction sites as well as in high-rises. The Z-folding makes possible a rapid operational deployment, even after the short lifting of the only partially unfolded packet of arms, and a high flexibility, in particular during concretizing of difficult to access locations, wherein dead space is substantially avoided both in awkward conveyance near to the vehicle as well as in concretizing in low spaces. The concretizing parallel to the work plane is possible with the multi-Z-fold. A bringing of the end hose close to the operator cabin is, however, achieved only at the expense of a relatively high unfolding height.
Further, a five-arm concrete distribution boom is known (WO 94/08111), of which mast arms 1, 2, and 3 are foldable against each other in the manner of a Z-fold while mast arms 3, 4, and 5, on their linkages D and E respectively in the same sense as mast arms 2 and 3 in the area of their articulation linkage C, are foldable against each other in the manner of a coil-fold. This mast configuration can be employed both in planar low spaces with overcoming of obstacles, as well as in high floors for concretizing with parallel hose guidance, and low fold out height.
The previously known mast configurations are so conceptualized, that they can be provided on a multi-axle vehicle chassis with extended rigid frame or on an articulated tractor-trailer. Motor vehicle regulations regulate the length and height of motor vehicles, which regulations stand in the way of a further increase of the range of the distribution mast.